Improvement in hot-air furnaces



' 2 sheets-sheet 2,

H. F.` HAYDEN. Hut-Air Furnaces.

Patented Nov. 3,1874.

THE GEAPHIGCOAFHOT 0 LITHA 35h44 PARK PLACLBLY` UNITEE 'STATES PATENT OFFICE.

HENRY E. HAYDEN, or wAsHrNeToN, DrsTEroT oE COLUMBIA.

IMPROVEMENT ISN Hor-AIR FuRNAcEs.

Specificationformingpart of Letters-Patent No. 156,568, dated November 3, 1874; application tiled September 29, 1874.

To all whom it may concern:

Be it known that I, HENRY F. HAYDEN, of the city vand county of Washington, District of Columbia, have invented certain new and useful Im prove ments in Hot-Air Furnaces of which the following is a full, clear, and exact description, reference being hadl to the accompanying drawing, making part of this specification, in whichlFigure l represents a plan or" top view of my improved heater, with the top of the casing removed. Fig. 2 isa perspective view of a portion of the inclosing casing, showing the inner side of said casing. Fig. 3 is a section throagh one of the smoke-fines. Fig. 4 is a vertical section on the line :v fr, Fig. 5; and Fig. 5 is a bottom view.

Similar letters of reference denote correspondin g parts wherever used.

My invention relates rto a novel construction and arrangement of parts of the furnace or heater, whereby a large amount of radiating surface, heated in a mild form, is secured, all highly-heated surfaces in the heatingchamber avoided, and the products of combustion very largely` utilized for heating purposes before they are allowed nally to escape into the smoke-due or chimney, as hereinafter explained. It further relates to 'a novel construction and arrangement of vaporizing attachment, whereby the usual objection to this class of heaters, caused by the dryness of the heat emitted, is effectually obviated, as

hereinafter fully set forth.

In the accompanying drawing, A represents the external casing or walls of the heatingchamber, which may be made of any usual material and of any desired form or configuration. Within this is placed the furnace or heater proper, consisting, in the main, of two parallel rectangular compartments or chambers, B C, connected by direct and return ilues b c. Within the chamberB is located the rev pot and ash-pit, with the intermediate grate D,

the walls E el c2 of said fire-pot and ash-pit being made of fire-brick, casteiron, or any usual or preferred material. The front, rear, and one side wall, el e2, of the lire-box terminate a short distance above the fuel-chute F, as shown in 1v Fig. 4, leaving the fire-pot open on top, while the wall E extends from the bottom to the top of the compartment or chamber B, forming a tight partition therein, giving two separate compartments, B1 B2, from the latter of which the products of combustion, escaping from the open top of the fire-pot, are excluded, except as hereinafter explained. The compartment B1, into which the products of combustion pass from the fire-pot, is connected with the compartment or chamber C by a number of horizontal dues, b, and the, compartment G again is partially divided by a partition piece or plate, C', extending from the top downward to a point midway, or thereabout, the height of said compartment, and underneath which the escaping products of combustion are compelled to pass, and said products of combustion are conveyed thence, through return-dues c, to'the chamber B2 of compartment B, from which they are permitted to escape through a y smoke-line, G, which conducts them to any desired point of discharge. The dues b c are, by preference, made velliptical in form, as shown in Fig. 3, as. affording a larger amount of radiating surface, and the joints thereof, as also all those of the compartments B C, may be covered with cement for preventing the escape of gas into the hot-air chamber, or, if preferred, the entire outer surface of thecompartments B and G, and ofthe ilues insidethe hot-air chamber, may be covered with a thin coating of cement, effectually preventing the escape of gas without interfering with the radiation of heat. Where any portion of the surface of the hues or of the chambers would be liable to be brought to a red heat the coating of cement should be increasedin thickness, so as to protect the hot-air chamber from the injurious eii'ects of such heat.

In the arrangement above described it will be seen that the gaseous products of combustion, escaping from the open top of the re-pot,

rst enter the compartment or chamber B1,

whence they pass through the iiues b to the compartment C, upon one side thereof, under the partition-plate G', to the opposite side, and through return-dues c to the compartment B2, and thence out through the smoke-flue Gr, parting at each step or stage of their progress with more or less of their heat, which is transmitted through the extended surface of said compartments to the air in the surrounding compartment until the temperature of the un consumed gases is reduced to nearly or quite the temperature ofthe atmosphere in said hotair compartment, `when they are allowed to es.

cape, as explained.

For causing the atmospheric air admitted to the hot-air chamber A to pass inward among the fines b and c, and in close proximity to the chambers B and C, deilectors a a are secured to the inner faces of the walls A, these detlectcrs passing horizontally around the hot-air chamber, and those, a', at the bottom, where the air is supplied in any usual way, forming a cold-air conduit varound the bottom of the heating-chamber, and from which the air passes into the chamber through slits or perforations ax. The detlector a runs in a similar manner around the hot-air chamber, in close proximity with the upper portion of the furnace, and prevents the cold air from ascending in right lines through the annular space between the furnace and its casing,

causing it to be deflected inward among the transverse lues b c, and into contact or close proximity with the heating-surfaces.

For the purpose of moistening the air as it is heated, and obviating the objections heretofore common to hot-air furnaces on account of the dry character of the heat produced, a large evaporating-pan, H,'is placed at the bottomof the heating-chamber, between the rectangular chambers B C, filling, if desired, the entire space between the bottoms of said chambers, and supplied with water in any convenient Way.

I is a rod or wire, extending across between the chambers B and C, at or near midway of their length, and from this rod is suspended a sheet of wire-gauze, K, made by preference of brass or galvanized wire to prevent corrosion. bent midway ofits length, with its .folded centerA resting on the rod I, and itsendsl reaching down into the evaporating-pan H.vr f `Within this folded sheet of wire-gauze is secured a layer or sheet of sponge, `or equivalent 1naterial which will, by its capillary attraction,^be come saturated with water from the pan H, while, at the same time, it is not liable to be injured b'y the heat when dry. vThis evaporating or vaporizing sheet is, by preference, suspended between the direct flues b and the return-fines c, where the heat is greatest, and the best eifect will be produced; but it may, ofcourse, be differently located, as convenierice or the requirements of the furnace may dictate.

By this arrangement it will be seen that,

. when the sponge becomes saturated, a large surface of water is exposed to the ascending volume of air, and the air, as it is heated, is thereby thoroughly moistened before it escapes from the heating-chamber, and from which it is conveyed to the rooms to be heated in any usual or preferred manner.

The chambers B and C are provided with man-holes at m n, closed by suitable doors, which aii'ord access to the chambers and dues for cleaning and repairs.

VIn practice, the furnace proper, as above described, should be first set up, and connection of the smoke-Hue made with the desired outlet, after4 which a tire should be built in it,

ffor the purpose of testing all the joints, and,

while' thus heated, the coating of cement should be applied to all the joints, as well as to such parts of the apparatus as would be at all liable to be brought toa red heat, under any conditions of use; and, thus applied, all danger of the crackingl or aking oft' of the coating of cement is eii'ectually avoided, while, at the same time, the apparatus is in condition for best ascertaining all leakage in the joints, and for applying the remedy. After this is done, the Walls or casing'of the heating-chamber may be built up, around the furnace in any usual or preferred manner, and of any suitable material.

The wallsor sides of the chambers B and (J and the dues b c may be all ot' sheet metal, this being protected in the portions most exposed to the direct heat of; the fire by the fire-brick or cast-iron of lwhich the repot. is composed, and by the coating of cement, as

explained. l A v I am aware that water has been carried up by mechanical appliancesfor the purpose of` extracting dust from,l and imparting moisture to, the atmosphere; but, in these appliances, so far as I am acquainted with them, the action was necessarily arbitrary and unvaryin g, while, with my evaporating apparatus, the conditions vary with the varying conditions of the atmosphere. Thus, when a high degree of heat is imparted to the atmosphere, and a rapid evaporation of the waterexposed is produced, a corresponding increase takes place in the capillary action of the vaporizer,

and vice versa, the amount of evaporation being at all times in proportionto the degree ot' dryness of the atmosphere, this effect being due to the porous nature ot' the sponge, upheld bythe open Wire-gauze, and in which, as the moisture is extracted, a constan tly-increasing surface is exposed to the action of the surrounding atmosphere.

Having now described my invention, what I claim as new, and, desire to secure by Letters Patent, is-

- 1. The divided rectangular compartment B, inclosin g the re-pot and ash-pit, as explained, in combination with the partially-divided compartment C and direct and return lines bc, all constructed, arranged, and operating substan, tially as and for the purpose specified.

2. The vaporizing apparatus composed of the eVaporating-pan H and of the wire-gauze and sponge, in combination with the furnace, arranged and operating substantially as described.

H. F. HAYDEN. 

